• Journal of Technologic Dentistry
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• v.8 no.1
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• pp.45-50
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• 1986

This study investigated the effect of burnout temperature on the castability of some nickelchromium alloys for porcelain fused to metal system and the effect of beryllium on the castability. Four alloys were evaluated: two contained beryllium(rexillium III, Super I) and two nonberyllium(Unibond, NNB). five burnout temperature, ranging form 100$^{\circ}F$ to 1800$^{\circ}F$, were aet at 200$^{\circ}F$ intervals for this study. The results obtained were as follows: 1. Beryllium-containing alloys were more castable than nonberyllium-containing alloys. 2. There was an optimal burnout temperature of range from 1400$^{\circ}F$ to 1600$^{\circ}F$ for the berylliumcontaining alloys studied. 3. An optimal burnout temperature for the nonberyllium alloys was not established.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.9
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• pp.4349-4371
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• 2019

Moldable parallel tasks are widely used in different areas, such as weather forecast, biocomputing, mechanical calculation, and so on. Considering the deadline and the speedup, scheduling moldable parallel tasks becomes a difficulty. Past work majorly focuses on the LA (List Algorithms) or OMA (Optimizing the Middle Algorithms). Different from prior work, our work normalizes execution time and makes all tasks have the same scope in normalized execution time: [0,1], and then according to the normalized execution time, a method is used to search for the reference execution time without considering the deadline of tasks. According to the reference execution time, we get an initial scheduling result based on AFCFS (Adaptive First Comes First Served) policy. Finally, a heuristic approach is used to improve the performance of the initial scheduling result. We call our method HSRET (a Heuristic Scheduling method based on Reference Execution Time). Comparisons to other methods show that HSRET has good performance in AWT (Average Waiting Time), AET (Average Execution Time), and PUT (Percentages of Unfinished Tasks).

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.297-297
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• 2022

홍수 발생으로 인해 야기되는 피해가 매년 일어나고 있으며, 현재 수재와 관련된 방대한 데이터가 축적되어 있어 이를 활용한 연구들이 진행되고 있다. 데이터를 기반으로 홍수 전후의 시공간적인 변화에 대한 다양한 분석이 가능하여 수재 대응에 유용하게 활용될 수 있다. 본 연구에서는 원격 탐지 및 재분석 데이터를 활용하여 파머 가뭄 지수(PDSI), 강우량, 유출량, 실제 증발산량(AET), 대기 온도 등의 수재와 관련된 요인들에 대한 지수분석을 통해 공간 변화를 파악하고 경향을 분석하였다. 이를 통해 자연 현상을 다루는 환경 영역에서의 데이터 기반 연구의 가능성이 확대될 수 있으며, 향후 연구에 활용하고자 한다.

• Korean Journal of Remote Sensing
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• v.36 no.6_1
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• pp.1465-1483
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• 2020

Evapotranspiration is a concept that includes the evaporation from soil and the transpiration from the plant leaf. It is an essential factor for monitoring water balance, drought, crop growth, and climate change. Actual evapotranspiration (AET) corresponds to the consumption of water from the land surface and the necessary amount of water for the land surface. Because the AET is derived from multiplying the crop coefficient by the reference evapotranspiration (ET0), an accurate calculation of the ET0 is required for the AET. To date, many efforts have been made for gridded ET0 to provide multiple products now. This study presents a comparison between the ET0 products such as FAO56-PM, LDAPS, PKNU-NMSC, and MODIS to find out which one is more suitable for the local-scale hydrological and agricultural applications in Korea, where the heterogeneity of the land surface is critical. In the experiment for the period between 2016 and 2019, the daily and 8-day products were compared with the in-situ observations by KMA. The analyses according to the station, year, month, and time-series showed that the PKNU-NMSC product with a successful optimization for Korea was superior to the others, yielding stable accuracy irrespective of space and time. Also, this paper showed the intrinsic characteristics of the FAO56-PM, LDAPS, and MODIS ET0 products that could be informative for other researchers.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.6
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• pp.518-524
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• 1990

Actual evapotranspiration was measured over rice paddy field by Bowen ratio heat balance method and based on this, investigated was the reliability of actual evapotranpiration estimation from Class-A Pan and small pan evaporation and reference evapotranspiration calculated by modified Penman-Monteith model. Crop coefficients based on Class-A Pan and small pan evaporation and reference evapotranspiration by modified Penman-Monteith model were averaged to be 1.57. 1.10 and 1.49 over the whole rice growing season, respectively. Their respective coefficients of variation were 28.7. 22.7 and 12.8 percent, respectively. Crop coefficient based on modified Penman-Monteith model varied in good agreement with the trend of leaf area development, being greatest around heading stage.

• Water for future
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• v.29 no.2
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• pp.235-247
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• 1996

Meteorological and soil water content data measured from semiarid watersheds of Lucky Hills and Kendall during the summer rainy and winter periods were used to study the interrelationships between the controlling variables of the evapotranspiration, and to evaluate the effects of variables on daily actual evapotranspiration (ET) estimation. Simple and multiple linear regression (MLR) analyses were employed to evaluate the order of importance of the meteorological and soil water factors involved. The information gained was used for MLR model development. Theavailable energy and vapor pressure deficit were found to be the important variables to estimate actual ET (AET) for both periods and at both watersheds. Therefore, the important variables of evapotranspiration process in these semiarid watersheds appear to be simply the components of energy term in available energy and aerodynamic term in vapor pressure deficit of Penman potential evapotranspiration (PET) equation.

• Macromolecular Research
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• v.16 no.5
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• pp.446-456
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• 2008

A recent theoretical approach based on the coupling of both the Flory-Huggins (FH) and the Association Equilibria thermodynamic (AET) theories was modified and adapted to study the miscibility properties of a multi-component system formed by two polymers (a proton-donor and a proton-acceptor) and a proton-acceptor solvent, named copolymer(A)/solvent(B)/polymer(C). Compatibility between polymers was mainly attained by hydrogen-bonding between the hydroxyl group on the phenol unit of the poly(styrene-co-vinyl phenol) (PSVPh) and the carbonyl group of the biodegradable and environmentally friendly poly(3-hydroxybutyrate) (PHB). However, the self-association of PSVPh and specific interactions between the PSVPh and the H-acceptor group (an ether oxygen atom) of the epichlorohydrin (ECH) solvent were also established in a lower extension, which competed with the polymer-polymer association. All the binary specific interactions and their dependence with the system composition as well as with the copolymer content were evaluated and quantified by means of two excess functions of the Gibbs tree energy, ${\Delta}g_{AB}$ and ${\Delta}g_{AC}$. Experimental results from fluorescence spectroscopy were consistent with the theoretical simulations derived with the model, which could also be applied and extended to predict the miscibility in solution of any polymer blend with specific interactions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.12
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• pp.1125-1134
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• 2013

Small cells such as pico or femto cells are promising as a solution to cope with higher traffic explosion and the large number of users. However, the users within small cells are likely to suffer severe inter-cell interference (ICI) from neighboring base stations (BSs). To tackle this, several papers suggest BS transmit power on/off control algorithms which increase edge user throughput. However, these algorithms require centralized coordinator and have high computational complexity. This paper makes a contribution towards presenting fully distributed and low complex joint BS on/off control and user scheduling algorithm (FDA) by selecting on/off pattern of BSs. Throughput the extensive simulations, we verify the performance of our algorithm as follows: (i) Our FDA provides better throughput performance of cell edge users by 170% than the algorithm without the ICI management. (ii) Our FDA catches up with the performance of optimal algorithm by 88-96% in geometric average throughput and sufficiently small gap in edge user throughput.

• Journal of the Korean Society of Costume
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• v.29
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• pp.23-38
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• 1996

The purpose of this study was to analyze the characteristics of the Minimal Art represented in the second half 20th century fashion. All the mode of dress worn this century have developed from the stimulus of a chang-ing society fired by new discoveries and a zest for the new and different. It would appear that even more dramatic changes will soon occur in our clothing styles the effects of which will be farreaching. Many of today's styles intended to dress our psyche rather than our bodies and this if fully understood by the new designers whose influ-ence will become increasingly more potent as we approach the new century. The highly developed material civilization resulted in human alienations environmental distruption, l By this fact human being of the 20th century was to overcome social com-plexity. Accordingly their search for simplicity was interested in the 60's style. Especially the formativeness of the 60s style was repre-sented in the second half 20th century fashion. In this paper it was focused that how the characteristics of the Minimal Art was expressed in the second half 20th century fashion. minimalism was a quest for basic elements repesenting the fundamental esthetic values of art. without regard to issues of content. At its most extreme it reduced art not ot an eter-nal essence but to an arid simplicity. "Primary Structure" the most suitable name suggested for this type conveys its two salient characteristics : extreme simplicity of shapes and a kinship with architecture. minimalist works are charcterized by huge dimensions coldness and absolute aesthetic neutrality. minimalist artists ambition is to de-fine through the most rudimentary materials such as plywood galvanized iron aluminum plastic and wood a new order of the space. The environment is just as important as the object itself. Similary the use of new tough materials. such as vinyl metal and plastic at late half of the 20th century fashion related to the formativeness of the Minimal Art. And the style of 20th fashion was holded the internal meanings in common the formativeness of the Minimal Aet thorough the various texture pat-tern silhouette etc.uette etc.

• Computers and Concrete
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• v.19 no.4
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• pp.429-434
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• 2017

Failure of basic structures material is usually accompanied by expansion of interior cracks due to stress concentration at the cracks tip. This phenomenon shows the importance of examination of the failure behavior of concrete structures. To this end, 4 types of mortar samples with different amounts of nano-silica (0%, 0.5%, 1%, and 1.5%) were made to prepare twelve $50{\times}50{\times}50mm$ cubic samples. The goal of this study was to describe the failure and micro-crack growth behavior of the cement mortars in presence of nano-silica particles and control mortars during different curing days. Failure of mortar samples under compressive strength were sensed with acoustic emission technique (AET) at different curing days. It was concluded that the addition of nano-silica particles could modify failure and micro-crack growth behavior of mortar samples. Also, monitoring of acoustic emission parameters exposed differences in failure behavior due to the addition of the nanoparticles. Mortar samples of nano-silica particles revealed stronger shear mode characteristics than those without nanoparticles, which revealed high acoustic activity due to heterogeneous matrix. It is worth mentioning that the highest compressive strength for 3 and 7 test ages obtained from samples with the addition of 1.5% nano-silica particles. On the other hand maximum compressive strength of 28 curing days obtained from samples with 1% combination of nano-silica particles.